When there is no route to an IPv6 dest addr, skb_dst(skb) points
to loopback dev in the case of that the IP6CB(skb)->iif is
enslaved to a vrf. This causes Ip6InNoRoutes to be incremented on the
loopback dev. This also causes the lookup to fail on icmpv6_send() and
the dest unreachable to not sent and Ip6OutNoRoutes gets incremented on
the loopback dev.
To reproduce:
* Gateway configuration:
ip link add dev vrf_258 type vrf table 258
ip link set dev enp0s9 master vrf_258
ip addr add 66:1/64 dev enp0s9
ip -6 route add unreachable default metric 8192 table 258
sysctl -w net.ipv6.conf.all.forwarding=1
sysctl -w net.ipv6.conf.enp0s9.forwarding=1
* Sender configuration:
ip addr add 66::2/64 dev enp0s9
ip -6 route add default via 66::1
and ping 66:7 for example from the sender.
Fix this by counting on the original netdev and reset the skb dst to
force a fresh lookup.
Signed-off-by: Stephen Suryaputra <ssuryae...@gmail.com>
---
net/ipv6/route.c | 22 ++++++++++++++++------
1 file changed, 16 insertions(+), 6 deletions(-)
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index e8c73b7782cd..3b026a310b3e 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -3772,23 +3772,33 @@ int ipv6_route_ioctl(struct net *net, unsigned int cmd,
void __user *arg)
static int ip6_pkt_drop(struct sk_buff *skb, u8 code, int ipstats_mib_noroutes)
{
- int type;
struct dst_entry *dst = skb_dst(skb);
+ struct inet6_dev *idev = ip6_dst_idev(dst);
+ struct net *net = dev_net(dst->dev);
+ int type;
+
+ if (netif_is_l3_master(skb->dev) &&
+ idev == __in6_dev_get(net->loopback_dev)) {
+ idev = __in6_dev_get_safely(dev_get_by_index_rcu(net,
IP6CB(skb)->iif));
+ }
+
switch (ipstats_mib_noroutes) {
case IPSTATS_MIB_INNOROUTES:
type = ipv6_addr_type(&ipv6_hdr(skb)->daddr);
if (type == IPV6_ADDR_ANY) {
- IP6_INC_STATS(dev_net(dst->dev),
- __in6_dev_get_safely(skb->dev),
- IPSTATS_MIB_INADDRERRORS);
+ IP6_INC_STATS(net, idev, IPSTATS_MIB_INADDRERRORS);
break;
}
/* FALLTHROUGH */
case IPSTATS_MIB_OUTNOROUTES:
- IP6_INC_STATS(dev_net(dst->dev), ip6_dst_idev(dst),
- ipstats_mib_noroutes);
+ IP6_INC_STATS(net, idev, ipstats_mib_noroutes);
break;
}
+
+ /* Start over by dropping the dst for l3mdev case */
+ if (netif_is_l3_master(skb->dev))
+ skb_dst_drop(skb);
+
icmpv6_send(skb, ICMPV6_DEST_UNREACH, code, 0);
kfree_skb(skb);
return 0;
--
2.17.1
